Switch and signal apparatus



(No Model.) Y 9 Shets-Sheet i.

G. WESTINGHOUSE, Jr., & J. G. SCHR'EUDER.

SWITCH AND SIGNAL APPARATUS. No. 446,159. Patented Feb- 10, 189 1.

INYENTD R WITN E SE8:

ms mmms vz'r'zns co., mo'rnirmq, WASHINDYON o c 2 MW. MR 43 W 6 E 8 R HO S G J & h S U 0 H G N I T S 3. W e 1 MG M 0 m SWITGH AND SIGNALAPPARATUS.

Patented Feb. 10,1891.

INVENT'O H Y gmii w WAMM (No Model.) QSheets-Sheet 3. G. WESTINGHOUSE,Jr., & J. G. SOHREUDER. SWITCH AND SIGNAL APPARATUS.

No. 446,159. Patented Feb. 10,1891.

md E INVENTCIH THE nnims rz-rsus m, wMo-u'ma, msuwcmn, a. c.

(No Model.) '9 Sheets-Sheet 4.

G. WESTINGHOUSE, J12, & J. G.. SCHREUDER. SWITCH AND SIGNAL APPARATUS.

No. 446,159. Patented Feb; 10,1891.

INVENTOR ZZQAWWJ MJUM '9 Sheets-Sheet 6.

(No Model) G. WESTINGHOUSE, J12, 81; J. G; SOHREUDER.

SWITGH AND SIGNAL APPARATUS.

No. 446,159. Patented Feb. 10,1891.

INVENTOR,

wrmzsses:

(No Model.) 9 sh-etkshet; 7. G. WESTINGHOUSE, Jr., 8; J. G. S-OHREUDER.

SWITCH AND SIGNAL APPARATUS. No. 446,159.

Patented Feb. 10, 1891.

WITNESSES:

ZQVENTOR,

W 8. MM

Att'y. 7

4:10am ravens w.,'mro-umo., wmmmrmu, n. c.

(No Model.) 9 Sheets-Sheet s. I

'G. WESTINGHOUSE, Jr.,& J. G. SO-HREUDER. SWITCH AND SIGNAL APPARATUS,

FIGJS.

mvsm'on,

luy ifi 1? amm/$ MM A (No Model.) -9 Sheets-Sheet 9.

G. WESTINGHOUSE, Jr., 8: J. G. SGHREUDER. SWITCH AND SIGNAL APPARATUS.

No. 446,159. Patented Feb. 10, 1891,

WITNESSES; I INVENTOR A? M w wwi 7 dwfiLJwuMb/r %M $u v HISWMLIAMEC AATTORNEY UNIT-en STATES PATE T 'QFFICE.-

GEORGE XVESTINGHOUSE, J R., AND JENS G. SCHREUDFR, OF PITTSBURG,PENNSYLVANIA.

SWITCH AND SIGNAL APPARATUS.

SPECIFICATION forming part of Letters Patent No. 446,159, dated February10, 1891. Applica ion file March 19, 1888. Renewed January 10, 1891.Serial No. 377,386. (No model.)

To aZZ whom it may concern.-

Be it known that we,- GEORGE W'ESTING- HOUSE, Jr.,a citizen of theUnited States, and JENs G. SOHREUDER, a subject of the King of Norway,both residing at Pittsburg, in the county of Allegheny and State. ofPennsylvania, have invented or discovered a certain new and usefulImprovement in Switch and Signal Apparatus, of which improvement thefollowing is a specification.

Theinvention herein relates to interlocking mechanism for controlling byfluid-pressure and electrically-pneuniatic or other pressure appliancesfor moving the switches and signals or other devices or appliances at adistance where a-return indication of completion of such movement isdesired, and the completion of such movement effects a locking of thecontrolling mechanism, the operation of said fiuid control being alsoregulated electrically; and in general terms the invention consists incertain combinations of rotatable or revoluble rollers or barrels, someof which are connected to valve mechanisms controlling the operation ofswitches and themselves dependent for full movement upon the switchmovements, said rollers being provided with insulated metallic strips solocated around the barrels or rollers as to require certainpredetermined positions of certain predetermined rollers for thecompletion'of the controlling electric circuits.

It also consists of mechanism for locking switch-operating levers, saidmechanism 'being operated by the signaLlevers, which are in turn lockedby electrically-controlled mechanism by the clearance of a signal andunlocked by the passage of the train from the section controlled by thecleared signal, all as more fully hereinafter described and claimed.

Figure 1 is a diagrammatic view showing a section of double tracks witha cross-over track and branch lines from each main line, together withthe appropriate home and distant signals, mechanism for operating theswitches and signals, the pipe-connections from the machine to suchswitch mechanism, and the electric circuits passing through the machinefor controlling thesignals. Fig. 2 is a front elevation of the machine,showing the switch and signal operating levers, a part of the frontplate being broken away to show the mechanical locking and valvemechanisms, partly in section and partly in elevation. Fig. 3 is a planview of the machine. Fig. at is a sectional elevation, the section beingtaken on the line ac 00, Fig. 2. Fig. 5 is a detail View, on an enlargedscale, of the electrically-actuated mechanism for locking theswitch-levers, showing the progressive steps in the operation ofshifting the switch. Figs. 6, 7, and 8 are plan, side, and end views ofthe electrically-actuated lever for locking the switch-lever. Figs. 9,10, 11, and 13 are diagrammatic views illustrative of the electriccircuits in different positions of the switches and signals and theiroperating mechanisms. Fig. 12 is a detail view, on an enlarged scale,

of the interlocking relay. Fig. 14 is a rear view of an indicator-boardcontaining minia- 7o ture tracks, showing the diiferent positions of theswitches operated by the switch-controlling mechanisms, and alsocontainingnumbered disks indicating approaching trains. Fig. 15 is asectional view on the line y y, Fig. 14:. Fig. 16 is a sectional detailview of a valve for releasing fluid-pressure for returning the numbereddisks to normal position. Fig. 17 is a perspective view of one of themake-and-break rollers controlling the signalcircuits. Fig. 18 isasectional view of one of the signal-levers. Figs. 19 and 20 are views ofthe circuit-breaker operated by the signalshifting mechanisms, theformer being arranged for a normally-closed circuit and the latter for anormally-open circuit.

The machine consists of an iron frame L, supported by a table L. In thisframe, near its rear end, are arranged a series of threeway-valvemechanisms 1 2 3 4, &c. Each of 0 these mechanisms consists of a case 3,having a conical opening therein for the reception of thecorrespondingly-shaped plug 4:, having grooves 5 and 6 for connectingthe--;; ports 7 and 8 alternately with the, inle't port 5 9and'exhaust-port 10, said ports 7, 8, 9, and 10, being formed in thecasing 3 The grooves 5 and (5 are made of such a length around the plugs4: that when the plugs are at center position the partitions between theI03 grooves shall cover the ports 7 and 8, as shown in Fig 2, and whenthe plug is/shifted, as

-plug is shifted.

hereinafter stated, to either side of its center 7 positionfluid-pressure will be admitted 'to either one orthe other of the ports7 and 8, depending upon the direction in which the The several casingsare formed with horizontal openings 11, registering with each other andforming a continuous passage under the casings through the machine forconducting fluid-pressure, said opening in each casing beingconnectedwith the inlet-port 9. The exhaust-port 10 in each casing isconnected with a similar passage formed by openings 12 in the casings.The passage or opening 11, formechas described, in the casings of thevalve mecha nisms of the series, is connected with a fluid-pressu rereservoir 13 by a pipe 14. (See Figs. 1 and 3.)

The ports 7 and 8 are connected with the valve mechanisms E, E, E and Econtrolling the switch-operating mechanisms F, F, F, and

F by pipes a a Z) l) c c.

The stems of the plugs l of the several valve mechanisms 1 2 8 at, &c.,are provided with operating handles or levers 15, and also withlocking-quadrants 16, having curved slots 17, (see Figs. 2 and 5,) thelower walls of the slots having notches 18 formed midway of the lengthof the slots. On the Valvecasings 3 are formed brackets 19, to which arepivoted the safety-latches 20, having their rear ends connected by rods21 to the armatures 22 of the electro-magnets 23, whereby the latchesare operated, as hereinafter described. The front ends of thesafety-latches engage the slots 17 in the quadrants 16, said latchesbeing held as against lateral movement bystuds 24, projecting upwardlyfrom the valve-casings. WVhen the circuit through .the magnet 23 isbroken, the Weight of the armature 22 holds the front end of thesafetylatch on a plane above the notch 18, so that the quadrant can befully reversed; but, as a full movement of the quadrant and itsconnections will, as hereinafter stated, complete an electric circuit,thereby rendering it possible to give asignal before the switches havebeen properly set, a tongue 25 is pivoted to the safety-latch 20 and isheld in normal position by means of spring-leaves 25, riveted to a ribon the under side of the latch and bearing at their free ends onopposite sides of the tongue near its rear end, as shown in Fig. 7 andby dotted lines in Fig. 6, said tongue projecting through a slot 27 inthe latch (see Fig. 8) and having its free end resting 011 top of thereduced end of the latch engaging the slot 17. This tongue is made ofsuch a thickness that when the latch is in normal position-4.10., thefront end of the latch elevated by the armature, as above stateda pin 26on the upper wall of the slot 17 will engage said tongue while thequadrant is being reversed, thereby preventing any movement of thequadrant beyond its center position greater than the amount of playallowed the tongue by the slot 27 in the safety-latch. This amount ofmovement is,

however, sufficient to so reverse the valve mechanisms 1 2 at, &c.; asto admit fluidpressure into that pipe which was in the previous positionof the valve, the exhaust-pipe, and thereby shift the switch by means offluid-pressure mechanism F. The unlocking of the switch-a steppreliminary to its movement-will, by the mechanism indicated at 124 126,&c., Fig. 1, close the circuit passin through the magnet 23, and themovement of the armature consequent thereupon will depress the front endof the safety-latch 20 into the notch 18 and free the tongue fromengagement with the. pin 26, thereby preventing any further movement ofthe quadrant and va-lve mechanism until the switch has been fullychanged and locked. The movement of the switch-locking mechanism breaksthe circuit through the magnet 23, thereby permitting its armature todrop and .raise the front end of the safety-latch from the notch 18 onthe opposite side of the pin 26, when the quadrant and valve mechanismmay be fully reversed.

In order to prevent any movement of the quadrant during the downwardmovement of the latch and tongue on the unlocking of the switch, asstated, the combined thickness of the tongue and latch is made greaterthan the distance between the lower end of the pin 26 and the bottomwall of the slot 17, so thatthe latch will engage the end of the notch18 before the tongue is freed from the pin.

In order to relieve the locking mechanism just described from shocks orstrains incident to a hurried operation of the machine and to regulatethe preliminary movement of the switch-controlling mechanism, the upperedge of the front plate 28, immediately in the rear of the levers 15, isformedinto a series of curved segments 2i provided with shoulders 30 and31, the distance between the shoulders 30 being equal to the length ofthe slots 17 and the distance between the shoulders 31 correspond ing tothe length of the notches 18. Onthe rear side of the levers 15 arearranged the sliding latches 32, having their lower ends constructed toengage the shoulders 30 and 31, the upper ends of said latches beingconnected to the stems of operating-handles 33, said stems passingthrough slots 34 in the upper ends of the levers 15. These latches areheld against the curved segments by springs 35, (See Fig. l.) Inshifting one of the levers the operator pushes on the handle 33 untilthe end of the latch drops into the notch forming the shoulders 3l,whichwill prevent any further movement of the lever until the operator raisesthe handle sufficiently to lift the latch clear of.

the shoulders. At the time the latch 32 engages one of the shoulders 31the quadrant l6, latch 20, and tongue 25 will bein the position shown bythe middle quadrant in Fig. 5. The operator allows the lever to remainat rest until the latch 20 and tongue 25 have been shifted in the mannerhereinbefore described to the position shown by the second IIO diagramfrom the right in Fig. 5. He then raises the handle 33 and shifts thelever until the latch 32 comes in contact with the shoulder 30, at whichtime the quadrant, latch 20, and tongue will be in the position shown bythe diagram at the right of Fig. 5.

Around the stems of the plugs 4 are arranged rollers 36, formed ofrubber, hard wood, or other non-conducting material,and on the rollersare secured a series of metal bands 37, passing partially around saidrollers, said bands being held in place by bending their ends inwardlyand inserting such bent ends into longitudinal deep grooves or slots 38,formed in the surfaces of the rollers.

On the frame L, beneath the rollers, is arranged a bed-plate 39,forlnedof rubber,hard wood, or other suitable insulating material, and alongthis bed-plate, at right angles to the rollers 36, are secured a seriesof metal strips 40, connected on one side of the machine to a commonmetal strip 41, secured on an end plate 42, of rubber, hard wood, orother suitable insulating material, so as to insulate the strip 41 fromthe machine, the opposite ends of these strips being connected toindependent binding-posts 43. These strips 40 are not continuous alongthe bed-plate, but are formed of two, three, or more sections, eachsection being provided at its ends with metallic springs 44, arranged tobear upon the rollers 30, in line with the bands 37, so that in certainpositions of the rollers the strips 40, springs 44,and bands 37 willform, except for breaks hereinafter described, a complete metalliccircuit from the binding-posts to the common strip 41. r

Parallel with the rollers 36, connected with the valve mechanism 1 2 3,&c., is arranged a series of rollers 45, similar in construction to therollers 36 and provided with metallic bands 37, partially surroundingsaid rollers, and arranged in certain positions of the rollers to engageor have electrical contact with the springs 44 of some of the strips 40,as

fully described in connection with the rollers 36. These rollers 45 arejournaled at one end of the machine in bearings '46, located between thevalve-casings 3 and, if desired, formed integral therewith. The oppositeends of the rollers are journaled in bearings formed in the front plate28 of the machine, as are also the rollers 36.

On the rear ends of the rollers 45 are secured quadrants 47, havingslots 48 formed therein, (see Figs. 2, 9, 10, and 11,) and within theseslots 48 are arranged the forward ends of locking-latches 49, which arepivoted on brackets 50 (see Figs. 3 and 4) and have their rear endsconnected by rods 51 to the armatures 52 of the electro-niagnets 53.These electro-magnets are included in electric circuits to behereinafter more fully described, which are made or broken by the changeof position of one or more signals included in oiie or morecombinationsof switches and signals and by interlocking relays which are controlledby the switch-operating mechansaid magnets 53 are broken the weight ofthe armature will raise the front ends of the locking-latches 49 betweenthe studs 54 on the upper walls of the slots 48, thereby preventing anymovement ofthe quadrants, (see Figs. 9 and 10,) or between the ends ofthe slots and the studs 54 when only a limited movement of the quadrantsis permitted.

The operating-levers 55 of the rollers 45 are slotted at their ends (seeFig. 2) for engagement with the stems of the handles 56 of thecrank-arms 57 of the shafts 58, which are journaled in suitable bearingsin the frame L, as shown in Figs. 2 and 4.

The handles 56 are provided with springacluated pins 59, adapted toengage a hole in the front plate 28 when the levers 55 and crank-arms 57are in line with each other, at which time the locking-latches 49 Willbe in line with the notch between the studs 54 and also with curvedslots 69011 both sides of the center position of the latch 49 andcrank-arms, these slots 60 being made of a leng h so proportioned inrelation to the distance between the studs 54 and the ends of the slots48 of the quadrants 47 that when the ends of the levers engage eitherthe ends of the slots or the studs 54 the pins 59 will bear against thecorresponding ends of the slots 60. This construction and arrangement ofdevices preserves the quadrants and latches from being injured byaccidental movements of the mechanism.

Beneath the rollers 36 and 45 and parallel therewith are arranged aseries of brackets 61 and 62, having notches formed in their up per andlower edges, respectively, for the reception of a series of locking-bars63, which are provided on the lower edges with a series of teeth adaptedto engage with the toothed segments 64, secured to the shafts 58, eachshaft being provided with a single segment 64 forengagement with one ofthe lockingbars. Above the locking-bars are arranged a series oflocking-clogs 65, pivoted at their rear-ends to the frame of themachines and having their front ends projecting through slots 66 in thefront plate 28, said locking-dogs being arranged in the vertical planepassing through the axis of the rollers 36 and adapted IIS when raised,as hereinafter stated,'to engage the tails 67 ot' the levers 15.

These lockingdogs are supported by the bars 63, which at suitableintervals are provided with notches or depressions 68 of suflicientdepthto allow the dogs to drop down below theline of movement of the tails67, the remaining portions of the bars being ofsuflicient height toraise the dogs into the path of movementof said tails. It will bereadily understood that as the switclroperatin g levers 15 are firstshifted to the right or left of the center position and then thesignal-levers are correspondingly moved, whereby the locking-bars 63 areso shifted as to raise the locking-dogs 65 from the depressions ornotches 68 into the path of movement of the tails 67, the levers 15cannot be reversed sufficiently far to change the switches until afterthe signal-levers 55 are returned to normal and the locking-dogs dropinto the notches 68. As the lockingdogs extend across the entire seriesof lockingbars, and as each bar is designed to operate only such of thedogs as are included in one combination, the bars 63 are so constructedas regards their upper edges that only those dogs included in any onecombination will be affected by the movement of the bars in suchcombination. In the present case this purpose is effected by notches inthe bars, such depressions or notches being of a length equal to thefull movement of the locking-bars. The operative notches (58, as theymight be termed, are so constructed, being of a length only a littlegreater than the thickness of the dogs, that the first movement of thelevers 55 from a center position will raise said dogs, thereby lockingthe levers 15 as against reversal until the levers 55 have been returned to normal or center position, as shown in. Fig. 2.

The lay-out or diagram of tracks employed for illustrating the inventionherein consists of the main lines M M, having the branches N N and thecross-over O, and the switches for the branches and cross-over m m and nand n, respectively. These several switches are operated by thefiuid-pressu re mechanisms F, F, F and F as shown in Fig. 1. Thesemechanisms are connected to the valve mechanisms E, E, E and E by pipes69, and-the valve mechanisms are connected to the machine-valves 1 2 34, &c., by pipes a a, Z) Z), and c 0, respectively, as hereinbeforestated.

In describing the signals and switches connected with the lay-cut shownin Fig. 1 trains will be supposed to be moving in the direction of thearrow as on track M and in the direction of the arrow 3 on the track M.The above-described system of tracks is provided with a distant signal70, governing the approach of trains on the track M to the switches mand n, the home-signal 71, governing the main line past the switches mand n, the route-signal 72, governing the branching line N, and theroute-signals 78 and 74 governing the movement of trains from'the branch1 to the main lines M and M, respectively. The distant signal 75 governsthe movements of trains on the track M as they approach the switches onand n in combination with the home-signal 76. The route-signals 77 and"'78 govern the movement of trains from the line M to the lines M and N,respectively. .The movement of trains from lines M to 1 and return isgoverned by what is commonly termed pot-signals 79 and 80. Thesemaphore-signals from 70 to 78, inclusive, are operated byany suitablefluid-pressure mechanism 81, preferably that described and claimed inLetters Patent No. 357,109, granted February 1, 1887, to GeorgeWVest-inghouse, Jr., said mechanism being connected to thefluid-pressure reservoir 13 by main pipes 82 and branches 83. The flowof pressure to and from the signal-operatin g mechanism 81 is controlledby electro-magnets, as shown in said patent, said magnets being includedin electric circuits controlled by the machine. The battery II isconnected by a suitable wire with a binding-post electrically connectedto the com mon strip 41, and the current passes from said strip 451through the strips 10, springs 44, and bands 37 on the rollers 36 and 45when said rollers have been properly adjusted, as will be hereinafterstated.- The current controlling the magnet of signal mechanism 81 onthe home-signal 76 passes from one of the binding-posts 43 by the wire81 to the magnet 85 of the locking-relay 86, and thence by the wire 87to the magnet on signal 76, and is there connected to branch pipe 83 ofthe system of fluid-pressure pipes which are connected to the oppositepole of battery H. The current controlling the magnet on distant signal75 passes from mgeof the binding-posts 4:3 by

the wire 88 through circuit-breaking mechanism 89, operated by themechanism 81 on signal 7 6, thence to a circuit-breaking track-relay 90,controlled by track-section 91, and thence to one pole of magnet ofsignal mechanism on signal 75, the opposite pole being connected tobranch pipe 83. The rails of insulated track-section 91 are connected atone end of said section to opposite poles of battery 7r and at theopposite end thereof to the magnet of relay 90. The current controllingthe magnet of the mechanism 81 of signal 77 passes from one of thebinding-posts 43 by the wire 93 through the magnet 9 1 of thelocking-relay 05, and thence by the wire 96 to the magnet on signal 77,from which point the current passes by the fiuidpressure pipes to thebattery H. The current controlling the magnet of the operating mechanism81 of the signal 78 passes from one of the binding-posts 13 by the wire97 to the magnet 98 of the locking-relay 99, and thence by the wire 100to the magnet on signal 78, whence it passes by the fluid-pressure pipesto the battery H. The currents controlling the magnets of the operatingmechanisms 81 of the signals 71 and 72 pass from two of thebinding-posts 43 by wires 101 and 102 to the magnets 103 and 101 of thelocking-relays 105 and 106, and thence by the wires 107 and 108 to themagnets on said signals, whence they pass by the fluid-pressure pipes tothe battery H. The currents controlling the magnets ot' the operatingmechanisms 81 of the route-signals 73 and 74 pass from two of thebinding-posts by the wires 109 and 110 to they magnets 111 and 113 ofthe locking-relays 112 and 114, thence by thewires 115 and 110 to themagnets of the route sig- IIO nals73 and 74, and from said magnets tothe wire 120 through the magnet in signal to.

battery H by the fluid-pressure pipes.

It will be observed that all the above-de scribed circuits start fromone side of the machine and that the battery H is connected to theopposite side of the machine. I Hence it is necessary that such of therollers 36 and 15 as are included in any combination should be incertain predetermined positions before any current can pass through saidcircuits to the magnets on the signal-operating mechanisms 81 of thesignals. The movements of the rollers 36, so far as a completion ofcircuits above described through their bands 37 is concerned, iselectrically controlled by the magnets L3, as hereinbefore described.One pole ofeach of these magnets is connected to the independentbinding-posts 121 and the opposite pole thereof to a common metallicstrip 122, insulated from the machine, said strip 122 being electricallyconnected to one pole of the battery H, whose opposite pole is connectedto the fluid pressure pipes, as shown in Fig. 1. The circuitjincludingthe magnet 23, controlling that oneiot the rollers 36 which is connectedto the valve mechanism 1, as hereinbefore stated, is formed by the wire123, leading from one of the bindingposts 121 to one part of thecircuit-breaking mechanism 12 the other part of said mechanism beingconnected to one of the fluidpressure pipes. This circuit-breakingmechanism12-1 is controlled by the locking-pin of the switch m and is soconstructed that the circuit is completed while the switch is unlockedand broken when the switch is locked in either of its positions.breaking mechanisms controlling the movements of the valve mechanisms onthe machine may be operated by any other moving part of the switch orits shiftin g mechanismas, for example, the deflector-rails, theswitchpoints of the piston of the fluid-pressure mechanism Fprovidedthat the circuit-breaking mechanism be so operated as to close thecircuit at the beginning of the switch-shifting operation and break thecircuit when the switch-points have been fully shifted. It is preferred,however, that the circuitbreaking mechanism be operated by thelocking-bolt, as stated, for the reason that the valve mechanism 1cannot be released, having once been locked by a completion of itscontrolling-circuit, until aft-er the switch-points have been fullyshifted and locked.

The circuit-breaking mechanisms 124, 126, 128, and 130 are constructedsubstantially as described in Patent No. 357,109, hereinbefore referredto, and in the diagrammatic view, Fig. 1, they are represented as movingin a These circuit.

direction parallel with the track-rails, and,

although shown for convenience outside of the rails, they are inpractice arranged between them.

The making and breaking of the switchcircuits, which are eitectedautomatically by the movements of the switch-locking bolts, cause thelatches to rise and fall, and thereby guide the operator and, indicateto him the position of the switches and the proper time for setting thesignals.

As the switches on and m, being opposite ends of the cross-over 0,should be operated together, the valves E and E of the switch operatingmechanisms F and F are connected, as shown, to the same valve mechanism1 of the machine, as shown in Fig. 1, and hence it is necessary that adouble electric lock controlledby the movements of both switches shouldbe applied to said valve mechanism 1. For this purpose a second slot 17,similar in construction to the slot 17, is formed in the quadrant 16, asshown in Figs. 2, 4c, and 5, and a second latch 20, similar to the latch20 in construction and function, is pivoted to a bracket or support 19,said latch being controlled by an electro-magnet 23. This electro-magnetis included in a circuit formed by a wire 125, passing from one of thebindingposts 121 to one part of the circuit-breaking mechanism 126, theother part of said mechanism being connected, as shown, to one of theflt'lid-pressure pipes. This circuit-breaking mechanism'126 iscontrolled by the locking-pin ot' the switch m in the manner abovedescribed in connection with the mechanism 124 of the switch m. I

The magnet 23 of the machine-valve mechanism 3, which controls theoperating mechanism F of the switch n through the medium" of the valvemechanism E is'included in the electric circuitformed by the wire 127,passing from one of the binding-posts 121 to one part of thecircuit-breaker 128, the other part of which is connected electricallyto the fluidpressure pipes. The magnet 23 of the valve mechanism 2,controlling the movements of the switch a, is included in the electriccircuit 129, passing the circuitbreaker 130 in a manner similar to thatabove described in the connection with the other switch-circuits.

The track-circuit controlled by the circuitbreaker 131, which iscontrolled'by track-section P of track M, is formed by the wire 133,lcading'from one part of the circuit-breaker 131 to the magnet 134E oflocking-relay 86, thence to the magnet 135 of locking relay 114, thenceto the battery h, and then to the other part of the circuit-breaker.

The track-circuit controlled by the circuitbreaker 136, which iscontrolled by the tracksection 1? of track M, is formed by the wire 138,leading from one part of the circuitbreaker to the magnet 139 of thelockingrelay 106, thence to the magnet 140 of lockingrelay 105, thenceto battery h, thence to magnets 1+11 and 1&2 of locking-relays 95 and99,

thence to one part of circuit-breaker 143, and thence back to thecircuit-breaker 136. It will be observed that the above-describedcircuit is also controlled by the track-section P through the medium ofthe circuit-breaker 143.

The track circuit controlled by circuit breaker 144,which is controlledby the tracksection P of track M, is formed by wire 145, leading fromone part of the circuit-breaker 144 to magnet 146 of the locking-relay112, and thence back to the other part of said circuit-breaker.

The movements of rollers 45 necessary for making or breaking the signalcircuits through the machine are controlled through the medium of thelatches 49 by the magnets 53, which are electrically connected. toindependent binding posts 147.

The circuit in which the magnet, or magnets 53, controlling themovements of the roller or rollers 45 for making or breaking thecircuits through the machine for signals governing train movements alongand from the track M, is formed by wire 148, leading from one of thebinding-posts 147 to circuit-breaking mechanism controlled by magnets 94and 141 of locking-relay 95, thence to circuit-breaking mechanismcontrolled by magnets 98 and 142 of locking-relay 99, thence to circuit-breaking mechanism controlled by magnets 85 and 134 onlocking-relay 86, thence to circuitbreaking mechanisms 149, 150, 151,and 152, controlled by signals 78, 77, 76, and 75, and thence to thefluid-pressure pipes, which are electrically connected to the battery7L2, in

cluded in the above circuit.

The number of signal-rollers 45 included in alocking-circuit dependsupon the number of train movements in any one lock-combination.

The circuit in which the magnet 53, controlling the movement of theroller 45 for making or breaking the circuits through the machine forsignals governing train movements along, to, and from track M, is formed by Wire 153, leading from one of the binding-posts 147 tocircuit-breaker controlled by magnets 140 and 103 in locking-relay 105,thence to circuit-breaking mechanism controlled by magnets 104 and 139on locking-relay 106, thence to circuit-breakers'154, 155, 156, 157, and158,

, controlled by signals 70 71 72 73 74, thence to fluid-pressure pipeand battery 7L3, thence .to circuit-breaking mechanism controlled bymagnets 111 and 146 on locking-relay 112, thence to circuit-breakingmechanism controlled by magnets 113 and 135 on locking-relay 114, andthence to locking-magnet 53.

The binding-post 43, forming the machine,

terminus of wire 88 to the distant signal 75,-

is connected to the common strip 41 by a con- 1 tinuo'us strip 40, inlieu of passing through strips 37 around the rollers; but it will beobserved that this circuit 88 passes through circuit-breaker 89,controlled by the home signal 76, and through the circuit breakeroperated by relay 90, controlled by insulated track-section 91, whichforms part of the circuit of the battery h. Hence it is necessary toclear the home-signal 76, thereby closing the circuit, 88 throughbreaker S9, and also that the circuit through the track-relay 90 shouldbe complete before the distant signal 75 can be cleared.

As one of the circuit-breakers in circuit 88 is controlled bytrack-section 91, the entrance of a car upon said section willby'cuttiug out the relay 90 break the circuit 38, thereby causing thesignal 75 to return to danger, and thus protect the rear of a trainpassing along the track M. It is sometimes necessary to allow a train topass the distant signal and move up to the home-signal; but, as in theabove-described arrangement, the distant sig nal is always cleared bysetting the home-signal at safety. A switch is placed in the circuit 88at the machine, so that said circuit may be broken by the operator,thereby returning the distant signal 75 to danger, while the home-signalis at safety. This machine-switch in circuit 88 may be an ordinary keyor one of the signal-rollers 45 not otherwise employed. Thismachine-switch may be employed in lieu of the track-section 91 forthrowing the distant signal to danger after the passage of the train.

In lieu .of interposing a circuit-breaker controlled by the home-signal71 in the circuit 117 of the distant signal 70, a circuit-breaker 159,controlled by thesignal 71, is interposed in the insulated track-section119, forming a part of the circuit of battery 7L5, said circuit alsoincluding the relay 11S, controlling cir cuit-breaking mechanism in thecircuit 117. The circuit 117, being a normally-open circuit, for thereason that the track-circuit 119 is also a normally-open circuit, beingclosed only when the signal 71 is cleared, the distant signal 70 willremain at danger until the circuit through the track-section 119 isclosed by the home-signal 71 going to safety, and the signal 70 willremain at safety until either the-signal 71 is set to danger or until acar enters the track-section 119 while the signal 71 is at safety, oruntil an operator opens a key on the machine, as described, inconnection with'circuit 88. t

The construction and operation of the locking-relays 86, &c., areclearly shown 011 an enlarged scale in Fig. 12, and by reference to saidfigure it will be observed that the signal and track circuits passthrough the magnets and 134 thereof, but that the locking-circuits areconnected to insulated binding-posts 160 and 161, the former beingelectrically connected to the armature 162 of the upper magnet 85, theother post 161 to the contact-point 163, attached to but insulated fromone arm of the bell-crank 164, the other arm of said bell-crank formingthe armature of the lower magnet 134 of the locking-relay. Within thescope of movement of the contact-point 163 is arranged a stationarycontact-point16 5,which is electrically connected to a contact-point 166on the spectacles 167 of the magnet 85. On the end of the vertical armof the bellcrank 164 is hinged a pawl 168, held by a spring 169 in linewith the arm of the bellcrank, but permitting of backward bending of thepawl when the vertical arm of the bellcrank is thrown to the left byclosing the circuit through the magnet 134. The operation of thislocking-relay is as follows: It being premised that signal-circuits arenormally open and the track-circuits normally closed, and while saidcircuits are in their normal condition, the above-described devices willassume the position shown,- thereby closing the locking-circuit. If nowthe signal-circuit should be closed, the armature 162 will be raised,thereby breaking the locking-circuit at the contact-point 166, and ifthe track-circuit be broken the locking-circuit will be broken at thecontact-point 165. When the armature 162 is raised by closing thesignalcircuit while the track-circuit is closed, the pawl 168 will bethrown to the left. the end of the pawl being moved into line with theinsulated bracket 170 on the armature 162, so that when thesignal-circuit is again broken the bracket will engage the step in theend of the pawl, thereby preventing the armature 162 from dropping downupon the contactpoint 166 and completing the locking-circuit as long asthe track-circuit remains closed. Hence, in order to close thelocking-circuit after it has been broken by closing the signalcircuit,it is necessary to break the track-circuit, thereby permitting itsarmature to drop and move the vertical arm of the bell-crank to theright, thus disengaging the notch in the pawl 16S and permitting thearmature 162 to drop upon the contact-point 166; but, as by the movementof the vertical arm of the bellcrank to the right the locking-circuit isbroken at the contact-point 165, the track-circuit must be againcompleted, thereby throwing the contact-points 163 and 165 togetherbefore the locking-circuit is closed.

In describing the operation of this plant reference will be hadprincipally to Figs. 1, 2, 5, 9, 10, and 11, and for the purpose of saiddescription it will be supposed that a train on track M, moving in thedirection of arrow 00 from a point to the right of the section of trackshown in Fig. 1, is to be shifted to track N.

Figs. 9, 10, and 11 illustrate the operation of the signals. thecircuits controlling and controlled by the signals, and theswitch-interlocking mechanism controlled by the signal-operatingmechanism only during the movement of the train from the right-hand endof M to and past the interlocking tracksectionP For this purpose it isnecessary that switches 71 and on should remain normal, as shown, andthat signals 7 6 and 75 should be cleared in the order named, until thetrain has passed track-sections 91 and P, the entrance of the train ontotrack-section 91 automatically shifting the distant signal 75 to danger,so as to protect the rear end of the train, said signal remaining atdanger until the train has passed off of track-section 91, when thesignal will return to and remain at safety until its controlling-circuitis broken by returning the home-signal 76 to danger, unless, as shouldalways be the rule, said controlling-eircuit is broken by the operatorby means of a key S, (see Fig. 9,) interposed in said circuit at themachine While the train is passing along track-section 91, in which casethe signal will remain at danger after the train has passed off oftracksection 91. The train having passed beyond the track-section P itisnecessary, in order that the train may pass over to N, that the switchesm, m, and a be shifted, the signal 77 be cleared, and all opposingsignals, including in this case all other signals shown, must be lockedat normal or danger.

As the switches m and 'n are normal or set for clear main line, it isonly necessary for the passage of trains to a point beyond thetrack-circuit P that the signals 76 and 75 should be cleared. This iseltected by throwing the second signal-lever 55 of the signalcontrollingmechanism B, Figs. 2 and 9, to the left, thereby so-turning its roller45 that one of the bands 37 thereon will come into contact with thesprings 44 on each side thereof, and so completing thecontrollingcircuit for the signal 76 through the machine, said circuitbeing formedby wires 84 and S7 and passing through magnet 85 in the locking-relay 86. The completion of this signalcircuit operates themechanism 81 of signal 76, so as to shift said signal to safety, and atthe same time closes the circuit for distant signal 75 at thecircuit-breaker 89, thereby operating the mechanism 81 at signal 75, soas to clear said signal. The completion of the circuit for signal 76through magnet 85 of locking-relay 86 raises the armature 162, (seelocking relay 86*,) thereby breaking the normally-closed locking-circuitformed by wire 148, which is also broken at circuitbreakers 151 and 152by the movement of signals 76 and75 to safety. This breaking of thelocking-circuit 148 permits the lockinglatches 49 to rise in their slots48 of quadrants 47, attached, as hereinbefore stated, to rollers 45,which are operated by the first and second signal-levers 55 ofsignal-controlling mechanism A, as shown in Figs. 2 and 9. The latch ofthe first signal mechanism A enters the notch between the lugs 54,thereby locking said mechanism in its center position as against anymovement for the reason that said lever controls, through circuitshereinafter mentioned, the signals 77, 78, and 74, which govern trainmovements in opposition to those controlled by signals 76 and 75,already cleared, as stated. Thelatch 49 of the second signal mechanismB, Figs. 2 and 9, enters the spacebetween the left-hand end of the slot48 in its quadrant '47 and one of the lugs 54, thereby locking saidmechanism as against its return to center position; but the distancebetween the lug 51 and the end of the slot is sufficient to permit ofsuch a movement of the roller 45 of said signal mechanism B as to movethe band 37 from contact with one of the springs 11, thereby breakingthe signal-operating circuit and returning the signals 76 and 75 todanger at the will of the operator; but the breaking of thesignal-circuit and the consequent return of the signals 76 and 75 todanger will not complete the locking-circuit 148, as the pawl 168 (seeFigs. 9 and 12) was moved under the bracket 170 by the action of thespring 169 15 when the armature 162 was raised, as hereinbefore stated,and said pawl will prevent the armature 162 from dropping onto thecontactpoint 166 until the circuit formed by wire 133 through magnet134: has beenbroken and then closed, either bythe passage of the trainonto and off from the track-section P or by the operator through themedium of a key placed in the circuit 133 at the machine for use inemergencies.

In Fig. 10 is shown the position of the parts of the machine included inFig. 9 after the signal mechanism B-has been shifted toward the rightfrom the extreme left-hand position shown in Fig. 9 until one of thelugs 54 encounters thelatch 49. This movementof the signal-controllingmechanism B will, as shown in Fig.10, break the signal-circuit 8-1 byturning the band 37 of said mechanism out of contact'with one of thesprings 11. As soon as this break occurs the signals 76 and 75 a returnto danger and the armature 16:2 of magnet 85 drops down, but cannot comeinto contact with the pin 166 on account of the pawl 168 engaging thebracket 170 on said 4 armature. (See locking-relay 86-", Fig. 10.)

As soon, however, as the train enters the unlocking'section P thetrack-circuit 133 is broken and the armature forming part of bell-crank164 drops,thereby disengaging the pawl 168 from the bracket of armature162,

thereby permitting said armature to drop into contact-point166,completing the locking-circuit at that point; but said circuit issimultaneously broken as .the contact-pin 163 was 5 drawn away from pin165 by the above-described movement of the bell-crank, as shown in relay86 Fig. 10. As soon, however, as the train passes off of the unlockingtracksection P the track-circuit133 is again completed and thebell-crank 164c is so moved as to bring the pins 163 and 165 intocontact, thereby completing the lockingcircuit- 1-18. (See Fig. 12.) Themagnets 53 being excited by the completion of the circuit 116, thelatches 49 are moved down below the path of movement of the lugs 54,thereby unlocking the signal mechanisms A and 13, whereupon the lattermay be returned to center or normal position, as shown in Fig. 11. Thisre- 5 turn-of the mechanism B to normal so moves the locking-bars 63 asto bring the notches therein in line with the dogs, which thereupon dropdown out of the line of movement of the levers of the switch-controllingmechanisms 1 2 &c.

In Fig. 13 are shown the positions of the bands 37 on rollers 36 or 45,controlling switches and signals for routes conflicting with the routegiven when said rollers are in the positions shown in Fig. 9. Byreference to said Fig. 13 it will be clearly seen by the positions ofthe bands 37 that the signal-circuit of which the bands 37 form a partcannot be completed until the rollers are turned; but, as hereinbeforestated, the shifting of the signal-lever to clear the signal for anygiven route locks up the levers and rollers control-1 ling anyconflicting routeas, for example, it is necessary, in order to give aroute in conflict with that given in Fig. 9, to shift theswitch-controlling mechanisms 1, 2, and 3 and the signal-controllingmechanisms A and B to the right in Fig. 9 in order to complete thesignalcircuit of which the bands 37 therein shown form a part but byreference to Fig. 9 it will be seen that said mechanisms are and willremain locked until the signal mechanism B has been returned to normal,(see Fig. 11,) thereby sending the signal controlled thereby to danger.The purpose of this locking of the signal-controllingmechanisms fromreturning to center position, although the signals have been returned todanger, is to prevent any movement of the switch-controlling mechanismswhich have been mechanically locked by the movement of the signal-lever55 of signal mechanism B through the medium of locking-bars 63 and dogs65, as hereinbefore described, until it is certain that the train haspassed beyond the last fouling-point in the combination, and this isindicated by the breaking and closing of the track-circuit 133, due tothe passage of the train over the unlocking -section P When theunlocking has been thus completed by the return of signals 76 and tonormal and the passage of the train over the unlocking-section P asabove stated, the signalcontrolling mechanism may be returned to centerposition, thereby unlocking the machine and all connections.

The train having passed the unlocking-section P as .above stated, it isnecessary,'in order that it may be shifted onto track N, to changeswitches on, m, and n and to clear the signal governing such route. Asthe switches m and m are controlled, as hereinbefore described, by thesame valve mechanism on the machinei. a, the one operated by that one ofthe levers 15 designated by 1 in Fig. 2-s'aid lever is shifted from theposition shown in Fig. 2, to the right until the latches 20 and 20, orrather the tongues 25 and 25, thereon encounter the pins '26 and 26 inthe slots 17 and l7" of the quadrant 16, as shown in the second quadrantfrom the left in Fig. 5. This movement of the lever shifts the valve 4so as to open the port 7 to the exhaust and the port 8 to thefluid-pressure supply.

Such change in the fluid-pressure so shifts the Valve mechanisms E and Eas to set the switch mechanisms F and F into operation. The firstmovements of the switch mechanisms withdraw the locking-bolts thereofand thereby so operate the circuit-breaking mechanisms 124 and 126 as tocomplete the switchlocking circuits formed by wires 123 and 125, passingthrough magnets 23 and 23. The excitation of these magnets produced byclosing the circuits causes, through the described connect-ions with thearmatures 22 and 22, the

forward ends of the latches and 20, with their tongues, to drop intonotches 18 and 18 of the quadrant 17,thereby permitting to clear thetongues and 25 from the pins 26 and 26 and pass to the opposite sidesthereof, as

shown in Fig. 5. The quadrant and its connections remain locked,however, by the latches 20 and 20 engaging the notches until after theentire switch movements have been completed and locked. The movements ofthe locking-bolts in locking the switch-rails break the switch-circuits123 and 125, thereby permitting the armatures 22 and 22 to drop andraise the latches 20 and 20 from the Y notches 1S and 18, whereupon thelever des 2 the lever designated 3 is also shifted to the right, theimmediate locking and unlocking of its quadrant- 16 and of the switch N,as described in connection with lever 1, being effected in the samemanner and order stated, as is also the closing of another break in thesignal-circuit by a strip 37 on the roller 36 connected to the lever Theswitches m, on, and n having been set,

as described, for the passage of the train tothe track N, it remains toclear the signal 77 and lock all opposing signals and such of theswitch-levers as are included in the combination or any othercombination conflicting therewith. In order to clear signal 77, thesignal-lever A, Fig. 2, is shifted to the left, thereby bringing a strip37 on the roller 45, operated by the lever A, into contact with springs44 on each side of the roller, thereby 7 completing the circuit ofsignal'77 through the machine, the roller 45, operated by lever B, whichis included in the same combination as lever A, having a strip 37 solocated thereon as to form electrical connection between springs 44 oneach side thereof and included in the circuit of signal 77 when thelever B is at normal or center position. Thecircuit of signal 77 fromthe machine to the signal passes by the wires 93 and 96 through themagnet 94 of locking-relay 95 to the signal- The complete move operatingmechanism 81, and the completion of the circuit, as described, operatessaid signal mechanism to shift the signal to safety, and also, byraising the armature 162 of the magnet 94, breaks the locking-circuit148, which is also broken by them'ovement of the signal 77 to safetythrough the circuitbreaker 150. This break in the locking-circuit causesthe latches 49 to rise, the latch of quadrant 47, connected to lever 13,entering the notch between the lugs or pins 54, thereby locking saidquadrant and its lever in center position, and the latch for quadrantconnected to lever A entering the space in slot 48 to the left of thelugs or pins 54', there'- by locking said lever A as against a return tocenter position until unlocked by the passage of the train onto and overthe track-section P, thereby opening and closing the circuit throughmagnet 141 of locking-relay 95, and thereby completing thelocking-circuit 148, provided signal 7 7 has been returned to danger inthe manner hereinbefore fully. set forth in connection with the movementof the train along track M; but the space in the slot 48 between theleft-hand end of said slot and the lugs or pins 54 is long enough topermit of such a movement of the roller 45, connected to lever A, aswill break the signal-circuit and return the signal 7 7 to danger. Thesignal 7 7 having been cleared, as above described, the train is free tomove from track M along the cross-over O to the track H, and thence ontothe track N. As

the train enters the section P the relay-operatin g circuit-breaker 143is cut out, thereby breaking the track-circuit 13S and releasing thearmature forming a part of bell-crank 164 of locking-relay 95 andpermitting the armature 162 to drop down onto contact-point 166, thuseffecting the first step'necessary, as hereinbefore described, forcompleting the locking-circuit 148 through said'locking-relay 95. Assoon as the train passes off of tracksection P the circuit 138 is againclosed, thereby causing the armature of the bellcrank 164 to be raisedand the contact-points 163 and 165 to be brought together, thuscompleting the locking-circuit'148 through lock ing-relay 95 andunlocking the signal-levers A and B, the signal 77 having been thrown todanger as soon as the train had moved past said signal by shifting thelever A the amount permitted by the distance between the lugs 54 and theend of slot 48, as hereinbefore stated.

It will be observed that lever C, controlling signal 73, forming a partof a combination different from that above described and in oppositionto the above-described train movements, is not included inlocking-circuit 148; but said signal cannot be cleared while theswitches m and m are reversed or set for the cross-over O, for thereason that a part of the circuit-controlling signal 7 3 is formed bystrips 37 on the roller 36 connected to the lever 1, controllingswitches m m, said strip belIO ing so located as to be incapable ofcompleting connection with the springs 44 of said signal-circuit untilthe lever 1 has been shifted to normal position, thereby causing the 5switches m and m to move to normal.

As an additional safeguard against theclearing of signal 73 while signal77 is cleared, the circuit-controlling signal 77 is formed in part by astrip 37, so located on the roller 45, conto nected to signal-lever O,as to require said signal-lever to be in center or normal positionbefore the circuit for signal 77 can be completed.

If nbw it should be desired to run the train from track N onto track M,and thence along said track in the direction indicated by arrow y, themachine having been unlocked by the passage of the train overtrack-section P, the signal-lever A is returned to normal or centerposition, thereby unlocking the switch-levers 1 and 3, which had beenmechanically locked by the movement of the signal-lever A to the leftinclearing signal 77 through the medium of locking-bars 63 and dogs 65 inthe manner hereinbefore fully described. The switchlever 1 is now turnedto the left or normal position, thereby shifting the switches m and m toclear main line; but the switch-lever 3 is not disturbed, the positioninto which it had- 0 been shifted for the train movement just describedbeing the same as required for the train movement desired-i. 6., forbranch line N. The movement of the switch-lever 1 and switches on m willbe accompanied by the 5 locking and unlocking movements controlled bycircuit-breakers 124 and 126, described in connection with the movementsof said lever and switches required for the train move-' ments lastreferred to. The switch N being to in proper position for the passage ofthe train from track N to M, it now remains to clear the signal 73, andthis is effected by turning signal-lever C to the right, therebycompleting signal circuit 109 through the machine 5 through the mediumof a properly-located strip 37 on the roller 45, operated by saidsignal-lever, a portion of said circuit having been previously completedwhen the switch-lever 3 was shifted to the right, as hereinbeforestated. The closing of circuit 109, which passes through magnet 111 oflocking-relay 112, breaks locking-circuit 153 through the raising ofarmature 162 of said magnet, said lockingcircuit being also broken bythe movement of signal 73 to safety through the medium of circuitbreaker158. The breaking of circuit 153 permits the armature 52 of the magnet53 pertaining to the signal-lever G to drop, thereby raising thelatch 49for locking said lever to rise in the slot 48 of the quadrant 47 intothe space between the right-hand end of said slot and the lugs 54, thuslocking said lever as against any return to center position, butpermitting such movement to the lever C and its roller 45 as will effecta break in the signal-circuit 109 for the purpose of returning signal 73to danger. The above-described movement of lever C mechanically locksthe switch-lever 3 through the medium of lockingbars 63 and dogs 65, andhence said switchlever and its switch 01 cannot be changed until thesignal-lever C has been returned to normal or center position. Thisreturn of the signal-lever to normal or center position cannot beeffected .until the latch 49 is dropped to the bottom of slot 48 ofquadrant 47, and such movement of therlatch 49 can only be effected byclosing the breaks in the lockingcircuit 153 by returning the signal '73to danger and the passage of a train over the tracksection P therebybreaking and closing the track-circuit 145, and so operating thebellcrank 164 of locking-relay 112 in the manner hereinbefore describedas to complete, the circuit 153 through said locking-relay. As thecircuits of signals 70, 71, and 72 are formed in part by strips 37, solocated on the roller 45 of leverO as to come into contact with springs44 only when the lever O is turned to the left, it is evident that suchsignals cannot be cleared until after the lever is unlocked from itsright-hand position by'the passage of trains over the unlockingtrack-section P, as hereinbefore described, the signal 73 having beenreturned to danger.

The machine having been unlocked by the passage of the train overtrack-section P as stated, it is necessary for the movement of the trainalong the line M in the direction of the arrow 3 after having passed outof branch line N, that the switch n should be returned to normal and thesignals 71 and be cleared. The latter can only be cleared in case thetrain has passed oft of the track-circuit 119,for the reasonhereinbefore stated, that the short-circuiting of this track sectionthrough the wheels of a car standing thereon will break signal-circuit117, thereby preventing the clearing thereof.

In order to return the switch n to normal, it is necessary to unlock itscontrolling-lever 3 by shifting the signal-lever O to center position,thereby so shifting the locking-bar 63 that the dog 65 will drop into anotch 68 therein, thus freeing the switch-lever 3, so that it may beshifted to the left or normal position and through the fluid-pressure ofmechanisms controlled thereby set the switch for main line. The operatornow shifts the signal-lever 3 to the left, thereby completing thecircuit formed by wires 101 and 107 through the machine and clearing thehomesignal 71. The movement of the signal 71 to safety closes thecircuit through track-section 119, by closing circuit-breaker 159, and,in case no cars are standing on said section, thereby closes the circuit117, controlling the distant signal 70, and shifts said signal tosafety, the circuit 117 having been completed through the machine bythemovement of the signal-lever O to the left, as hereinbefore described.As the circuit 107 passes through magnet 103 of locking-relay 105 theclosing of said circuitraises t-he armature 162 of said magnet from thecontact-point 166, thereby breaking the lockin g-circuit 153, which isalso broken by the movement of signal 71 to safety throughcircuit-breaker 155 and locking the signal-lever O as against return tocenter position in the manner fully described in connection with theclearing of signal 73.

As the roller 45, connected to lever C, is provided with astrip37,torming part of the circuit-controlling signal 73, and said strip 37is so located that said signal-circuit is completed only when said leveris turned to the right, it is evident that said opposing signal 73cannot be given while signal-lever is locked to the left, as described;and as it is necessary that the signal 71 should be returned to danger,thereby closing the break 155, and that the track-circuit 138 should bebroken and then closed by the passage of the train over track-section P,in order that lever 0 may be unlocked and turned to the right, it isevident that the opposing signal 7 3 cannot be given until after thetrain has passed all. fouling-points in the arrangement of tracks shownin Fig. 1. Although the strip 37 on roller l5 of lever O is so locatedas to complete, so far as said roller is concerned, the

circuit-controlling signal "2 when lever C is turned to the left, itwill be impossible to clear the signal 7 2, for the reason that aportion of the circuit-controlling signal 72 is formed by a strip 37 solocated on the roller 36 of lever3 as to complete said signal-circuitonly when the leverS has been shifted to the right for reversing switch01'.

The arrangement of tracks and switches, together with theircontrolling-signals, the several electric circuits for controlling theposition of signals, and the operating-machine, as shown in the drawingsand hereinbefore described, is employed for the purpose of illustratingthe several features of the invention herein as they maybe applied inuse; but the invention is not limited to the arrangement, number, orcombinations of switches, signals, and controlling-circuits shown, asthe skilled operator will be enabled from the foregoing to apply theinvention as the various and continually-changing conditions of use mayrequire.

. Above the machine is arranged a board (see Figs. 2 and 4:) havingminiature rails 172 arranged thereon in correspondence with the tracksand switches controlled b ythe machine, the switches being representedby short sections 173, each having one end free to move, and theopposite secured to a pin 174:, passing through the board 171, and onthe end of the pin 174, projecting through the rear side of the board,is secured a crank-arm 175. (See Figs. 4: and 14.) As each switch isrepresented by two of the sections 17 3, one in each rail, thecrank-arms 175 are connected in pairs, as shown in Fig. let, by bars176, so that each of the sections will be simultaneously swung out ofline with the rail 172 and into line with each other, as shown in Figs.2 and 14. One of the crank-arms 175 is connected by a rod 177 to a lever178, so pivoted on the board 171 that one of its ends extends down intothe line of movement of the lugs 179, formed on the quadrant 16,connected to the switch-controlling mechanisms of the machine. Theselevers 178 are held normally in a center position by springs 180, asshown in Fig. 14, and the sections 173, forming a pair, are so connectedby the rods 177 to the levers 178 and to each other that when the leversare held in center position, as above stated, the sections are held outof line with the main rails andwith each other, as shown in Fig. 14-.These levers 178 are shifted to one side or the other by the lugs 179 inaccordance with the movementof the quadrants, the lugs being so locatedon the quadrants as not to engage the levers until the quadrantsapproach closely the limits of their movements, and as the quadrantscannot, on account of the locking mechanism hereinbefore described,approach closely the limits of their movements until the switch-railshave been shifted and locked the sections will, after the first movementof the quadrants in shifting a switch, remain in their normal or brokenposition, as stated, until after the switchrails have been fully shiftedand locked, thereby permitting of the completion of the movement of thequadrants.

Any known devices operated by train movements along the track to makeand break electric circuits may be employed in lieu of the insulatedtrack-sections herein described, and such devices are hereby included asthe full equivalents of the track-sections and fully within the spiritand scope of the invention herein.

Each line of track, whethermain or branch line, forming the system undercontrol of any machine is duly numbered, and in order to notify theoperator on which line of track a train is approaching short sections ofthe tracks at a distance of a mile and a half or two miles are insulatedfrom the rest of the tracks and form parts of normally-closed electriccircuits, which are opened by the passage of a car over the insulatedtrack-sections, thereby closing a normally-open circuit operating anelectric bell near the machine and causing the magnet 181 to attract thearmature 182, thereby withdrawing said armature from engagement with afinger 183, connected to the disk 184, thereby permitting said disk todrop down into line with the opening 185 through the board 171, saiddisk being pivotally mounted on therear side of said board, as shown.

Each of the rails or lines 172 on the indicator-board is provided withan opening 185 and a properly-nu mbered disk 184, so that the operatorwhen the bell is rung needs only to glance at the board to ascertainwhich of the tracks and signals he must prepare for the approachingtrain.

In order to return the indicator-disks to

